Many conventional control systems include automation control, such as automated landing of individual or linked formations of aircraft, automated control of nuclear power plants, automated piloting of ship navigational systems, etc. Automation control is generally reliable but not infallible, as there is always the chance of one or more automation control failures due to unforeseen or unusual circumstances, hardware failures, communication link failures, sensor failures, etc. Since the cost of failure is unacceptably high, conventional control systems include human operators as the ultimate backup to ensure safe operation. In certain events, for example, when the automation control system fails, the human operator can take manual control to ensure safe operation of the control system.
Conventional control systems often assume that the human operator is not attentive and must have the human operator's attention directed to potential failures by sounding obvious alerts (alarms, flashing lights, etc.) when the control system detects a potential failure. This potential failure may be computed using various conventional methods, such as statistical models to determine when to sound such alerts, given the probability of failure and operating conditions. These conventional control methods for sounding alerts have many problems because quite often the statistical models must be sensitive enough to detect potential failures, however, such sensitivity can produce frequent false alerts. Such frequent false alerts can condition human operators to delay response to a failure while they determine on their own whether a failure has in fact occurred. Such delays can have detrimental consequences when a control system failure requires the human operator's immediate attention and/or corrective input.